Folding case with rotating side cover

ABSTRACT

The present invention relates to a protective case for foldable mobile devices. The folding case according to the present invention comprises a first case and a second case, wherein the folding case further comprises a side cover which rotates by an elastic part as the foldable mobile device is folded or unfolded, and provides a full protection for the entire foldable mobile device including each corner of its hinge part. The folding case according to the present invention covers the hinge part smoothly without any unfavorable space or gap, and it provides the satisfaction with the use and the beauty of the overall appearance as the users would conceive that the two separated case parts and the hinge part operates as if those parts form one united case.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. provisional patent applicationNo. 62/511,280, filed on Sep. 29, 2020, the disclosures of which areincorporated herein by reference in their entirety.

FIELD OF THE INVENTION

The present invention relates to a protective case for electronicdevices such as mobile smart phones and cellular phones. Specifically,the present invention relates to such protective cases for foldablemobile electronic devices.

BACKGROUND OF THE INVENTION

A mobile electronic device is a computing device that users are able tocarry all the time. Since the users carry a mobile device for theirdaily life, it is prone to be damaged due to their careless treatmentsand unintentional drops. Thus, protective cases for mobile electronicdevices have been widely used to minimize the damage. Such protectivecases generally protect the mobile electronic device from the outsideimpact by embracing the exterior of the device with the shell-likestructure of the case components.

A typical display system for a mobile electronic device has adopted aflat panel display. However, a flexible display has been recentlydeveloped, which enables a screen to be folded or bent, and applied tomobile electronic devices. If the flexible display is applied to themobile electronic device, the device itself can be folded or bentaccordingly. Since the foldable mobile electronic device could providevarious innovative applications by its shape transition, there has beena growing expectation in the IT (Information Technology) industry.

However, one of the disadvantages of the foldable mobile device is thatit is hard to install a protective case thereon due to the shapetransition by the flexible display being folded or bent. In other words,the case may be easy to be installed on the non-transitionable portionof the foldable mobile device, whereas the case may be difficult to beinstalled on the transitionable portion due to its shape transition.

Since the cases currently available are difficult to be placed on thefoldable mobile device, especially on its hinge part which enables thefoldable mobile device to be folded or bent, it is hard to provide afull protection to the device from outside impact. In particular, sincethe hinge part is one of the most fragile components of the foldablemobile device, a case that protects the hinge part and the overalldevice regardless of the shape transitions is required to provide userswith the full protection of the foldable mobile device.

There is a case system commercially available that is designed toprotect a foldable mobile device, including the hinge part, byconnecting two separated case parts with an elastic linear protectivecomponent. However, the elastic linear protective component between twocase parts does not fit tightly to the hinge part depending on theposition of the flexible display of the foldable mobile device. If itdoes not fit tightly, the full protection of the foldable mobile device,the hinge part thereof in particular, cannot be achieved. Besides, thosetwo case parts are not assembled in a smooth way, and it fails toprovide the satisfaction with the use and the beauty of the overallappearance. Furthermore, each corner of the hinge part is notsufficiently covered by the elastic linear component, so that the fullprotection of the foldable mobile device could not be assured.

SUMMARY OF THE INVENTION

The folding case according to the present invention comprises a firstcase and a second case, wherein the folding case further comprises aside cover which rotates from a first position to a second positionaround the rotation axis of the first case, and an elastic part whichprovides an elastic force for the side cover to return to the firstposition. The side cover rotates as the foldable mobile device is foldedor unfolded.

The present invention provides a full protection for the entire foldablemobile device including each corner of its hinge part. The folding caseaccording to the present invention covers the hinge part smoothlywithout any unfavorable space or gap, and it provides the satisfactionwith the use and the overall aesthetic appearance as the users wouldconceive that the two separated case parts and the hinge part operatesas if those parts form one united case.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects and advantages of the presentinvention will become better understood with reference to theaccompanying drawings, wherein:

FIG. 1 demonstrates a representative foldable mobile device;

FIG. 2 shows a folding case according to an embodiment of the presentinvention;

FIG. 3 shows a folding case according to an embodiment of the presentinvention;

FIG. 4 shows representative features of a folding case according to anembodiment of the present invention;

FIG. 5 shows a first case and a side cover of a folding case accordingto an embodiment of the present invention;

FIG. 6 shows a first case and a side cover of a folding case accordingto an embodiment of the present invention;

FIG. 7 shows a bottom sectional view of a folding case according to anembodiment of the present invention;

FIG. 8 demonstrates a detailed connecting structure between a first caseand a side cover of a folding case according to an embodiment of thepresent invention;

FIG. 9 shows a support of a folding case according to an embodiment ofthe present invention;

FIG. 10 demonstrates steps of connection between a first case and a sidecover of a folding case according to an embodiment of the presentinvention;

FIG. 11 shows a folding case in a closed state according to anembodiment of the present invention;

FIG. 12 shows a folding case in an open state according to an embodimentof the present invention;

FIG. 13 shows a folding case in an open state according to an embodimentof the present invention;

FIG. 14 shows a bottom sectional view of a folding case according to anembodiment of the present invention;

FIG. 15 demonstrates that a side cover of a folding case is used as astand according to an embodiment of the present invention; and

FIG. 16 shows a button part of a folding case according to an embodimentof the present invention.

DETAILED DESCRIPTION EMBODIMENTS OF THE INVENTION

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings, which form a part of this disclosure. It is to be understoodthat this invention is not limited to the specific devices, methods,conditions or parameters described and/or shown herein, and that theterminology used herein is for the purpose of describing particularembodiments by way of example only and is not intended to be limiting ofthe claimed invention.

The terms used in the description are to explain the embodiments, butnot to limit the present invention in any way. The term ‘comprise,’‘comprises,’ or ‘comprising’ is used to describe that a subject matteris constituted from a combination of features or characteristics. Thus,it should be understood that it does not exclude one or more additionalfeatures or the combination thereof.

FIG. 1 demonstrates a foldable mobile device(M). According to FIG. 1,the foldable mobile device(M) to which a folding case(C) is appliedaccording to an embodiment of the present invention comprises a firstbody(10), a second body(20) and a hinge part(30).

Each of the first body(10) and the second body(20) of the foldablemobile device(M) does not change its shape. The hinge part(30) is afeature that allows the foldable mobile device to be folded or bent.However, the hinge part(30) is prone to be damaged by the impact fromoutside. Therefore, it is important to keep the hinge part(30) safe fromthe outside impact.

FIGS. 2 and 3 show a folding case(C) according to an embodiment of thepresent invention. According to FIGS. 2 and 3, the folding case(C)according to an embodiment of the present invention comprises a firstcase(100), a second case(200), and side cover(300).

The first case(100) is installed on the first body(10) of the foldablemobile device(M). The first case(100) protects the foldable mobiledevice(M) with its width higher than one surface of the foldable mobiledevice(M). The first case(100) may comprise an edge part(110) whichcovers each corner of the first body(10). The edge part(110) protectsthe first body(10) with its width higher than one surface of the firstbody(10).

The edge part(110) according to an embodiment comprises a tunnel(111).The tunnel(111) is an aperture that is formed by at least a portion ofthe edge part(110) being opened or curved. The tunnel(111) is a featureto maintain that at least a portion of a surface of the first case(100)is not covered by the edge part(110). The edge part(110) embraces eachcorner of the first case(100), and covers a portion of the surface ofthe first case(100). If a speaker module is located in the portioncovered by the edge part(110), the sound from the speaker module may nottravel outside. If the tunnel(111) is established on the location of theedge part(110) that corresponds to the speaker module, the sound fromthe speaker module would travel through the tunnel(111). Accordingly,the sound from the foldable mobile device(M) can travel outwards clearlywithout being covered by the edge part(110).

The second case(200) is installed on the second body(20) of the foldablemobile device(M). The second case(200) protects the foldable mobiledevice(M) with its width higher than one surface of the foldable mobiledevice(M).

The second case(200) comprises a bulge part(210). The bulge part(210) isformed higher than the height of a camera module of the second body(20).If the camera module is located on the second body(20), it may causescratches on the camera lens due to the height of the protruded cameramodule even with the protective case. The bulge part(210) is formedhigher than the height of the camera module at the locationcorresponding to the camera module, and keeps the camera module safefrom scratches.

The side cover(300) protects the hinge part(30) of a foldable mobiledevice(M). According to FIG. 3, the side cover comprises a pattern part.The pattern part plays a role in the non-slip function for the sidecover(300) which has a round shape pattern for a better grip. In anembodiment of the present invention, the pattern part may have variouspatterns, including a diagonal pattern, to achieve the non-slip effect,but not limited thereto.

FIG. 4 shows representative features of a folding case according to anembodiment of the present invention. According to FIG. 4, the sidecover(300) is connected to the first case(100). However, the firstcase(100) and the second case(200) may be separated. The previousfolding cases have a connecting part that connects two case parts toprotect the hinge part(30) of a foldable mobile device(M). In suchcases, two case parts are not connected smoothly due to the unfavorablegap over the connecting part when the folding case is unfolded, and thehinge part(30) cannot be properly protected. However, the presentinvention provides a case system that the first case(100) and the secondcase(200) are separated, and the side cover(300) connected to the firstcase(100) rotates to protect the hinge part(30). Therefore, thestructure of the present invention is completely different from theprevious folding case that has a connecting part to connect two caseparts.

The side cover(300) comprises a cover part(320) that covers up to thecorner of the hinge part(30) of the foldable mobile device(M). Theconnecting part of the previous cases could not protect the corners onthe side of the hinge part(30). However, the present invention safelyprotects the corners on the side of the hinge part(30) by the sidecover(300).

The folding case(C) according to an embodiment of the present inventioncomprises a pad part(500). The pad part(500) touches at least a portionof the foldable mobile device(M). The pad part(500) absorbs the forcefrom the outside that may impact the folding case(C). The pad part(500)may be made of the substance that has a tight adhesive force andelasticity. Thereby, it may protect the foldable mobile device(M) moreeffectively, and prevent it from minute damages. If the case is directlycontacted with the foldable mobile device(M) without the pad part(500),it cannot absorb the impact effectively. Furthermore, the direct contactof the case may cause scratches on the foldable mobile device(M). Thepad part(500) according to an embodiment of the present inventionabsorbs the impact effectively by allowing the case to maintain adistance from the foldable mobile device(M). Also, the pad part(500)protects the foldable mobile device(M) from the scratches, and at thesame time, it improves the tight adhesive force to reduce the gapbetween the foldable mobile device(M) and the case.

The folding case(C) according to an embodiment of the present inventioncomprises air rooms(400). The air rooms(400) absorb the impact to thefolding case(C) from one side covering the corner of the foldable mobiledevice(M). The air rooms(400) are formed at the portion that meets thecorner of the foldable mobile device(M). The air rooms are formed at theportion that meets the corner of the first body(10) for the firstcase(100), and at the portion that meets the corner of the secondbody(20) for the second case(200). When a case encounters an impact fromoutside, the empty space of the air rooms(400) minimizes the physicalforce that would be directly delivered to the foldable mobile device(M).Since the corner portion of the device is prone to damage, the presentinvention provides a secondary protection to the foldable mobiledevice(M) by the air rooms(400) in addition to the primary protection bythe case.

The folding case(C) according to an embodiment of the present inventionmay be made of hard material and soft material. By combining the hardand soft material, the folding case(C) may have both properties: aresistance from the impact and a absorbance of the impact. Especially,the frame of the first case(100) and the second case(200) is made ofsoft material to absorb the impact to the case. Depending on theembodiments, polycarbonate as the hard material and TPU(ThermoplasticPolyurethane) as the soft material, respectively, may be used. However,if the properties are satisfied, the materials for the first case(100)and the second case(200) are not limited to the material above. Thedouble injection moulding may be used to combine the hard material andthe soft material.

FIGS. 5 and 6 shows the first case(100) and the side cover(300) of afolding case(C) according to an embodiment of the present invention.According to the FIGS. 5 and 6, the side cover(300) rotates along therotation axis of the first case(100). The side cover(300) rotates from afirst position to a second position. FIG. 5 shows the side cover(300) inthe first position, and FIG.6 shows the side cover(300) in the secondposition after rotation. The first position is the state that the sidecover(300) is closed, and the second position is the state that the sidecover(300) is open as wide as possible.

FIG. 7 shows a bottom sectional view of a folding case according to anembodiment of the present invention. The side cover(300) rotates with anangle corresponding to the angle as the foldable mobile device(M) isfolded or unfolded. The side cover(300) is able to rotate with an anglethe same or wider than the angle that the foldable mobile device(M)rotates. It is because, if the angle that the side cover(300) rotates issmaller than the angle that the foldable mobile device(M) rotates, theside cover(300) may interfere with the folding or unfolding of thefoldable mobile device(M). According to FIG. 7, the angle between thefirst position and the second position may be from 87° to 93°.Preferably, the angle between the first position and the second positionmay be from 88.3° to 90°. It is derived by the repetitive simulation,and it corresponds to the optimal angle that the side cover(300) couldrespond to the angle that the foldable mobile device is folded orunfolded. Depending on the embodiments, the angle between the firstposition and the second position could be established depending on therotatable angle of the foldable mobile device.

FIG. 8 demonstrates a detailed connecting structure between a firstcase(100) and a side cover(300) of a folding case(C) according to anembodiment of the present invention. According to FIG. 8, the foldingcase(C) according to an embodiment of the present invention comprises anelastic part(120). The first case also comprises a support(150). Theelastic part(120) provides an elastic force that enables the sidecover(300) to return to the first position. The elastic part(120) islocated at one side of the first case(100), and connected to the sidecover(300). The elastic part(120) enables the side cover(300) to rotatealong with the rotation axis of the first case(100), and to return backto the first position. The support(150) fixes or supports at least aportion of the elastic part(120). More specifically, while at least aportion of the elastic part(120) is supported by the support(150), theelastic force that enables the side cover(300) to rotate back to thefirst position along with the rotation axis of the first case(100) isdelivered to the side cover(300) that is connected to the elasticpart(120).

Meanwhile, the support(150) functions that the first case(100) is not tobe pushed back or distorted. If the edge part (110) of the first case(100) is thin enough not to interfere with the display module of thefoldable mobile device(M), it is easy to be pushed back or distorted bythe force applied to the fold case. However, since the support(150)fixes or supports one side of the edge part(110), the first case(100) ismore stably installed on the first body(10), and protects the foldablemobile device(M). Preferably, the support(150) is made of steel.However, it is not limited to the aforementioned material, but variousmaterials that satisfy the requirements for the strength to support theelastic part(120) and the first case(100) could be used.

Hereinafter, an embodiment that includes a spring in the elasticpart(120) is described. The feature in the elastic part(120) is notlimited to the spring, but various components that provide an elasticforce could also be considered.

The elastic part(120) comprises a pair of torsion springs separatedapart while being connected by an arm. The pair of torsion springscomprises a first torsion spring(121) and a second torsion spring(123).The first torsion spring(121) and the second torsion spring(123) arepositioned in parallel. That is, a pair of torsion springs separatedapart in parallel, while being connected by an arm. The pair of torsionsprings are connected to each other with a first arm, while a second armis connected to the side cover(300).

The elastic part(120) comprises a ring part(125). The ring part(125) isformed by a pair of torsion springs that are connected to each other byan arm. In an embodiment of FIG. 8, the first arm of a pair of torsionsprings are connected to each other to form the ring part(125). Althoughthe ring part(125) in FIG. 8 is linear, the ring part(125) may includeany shape of the arm that connects a pair of torsion springs separatedapart.

The side cover(300) comprises a protrusion(310) which has a pinhole(311). A pin(130) is inserted inside the pin hole(311), whichenables the side cover(300) to rotate along with the rotation axis ofthe first case(100). The pin(130) is inserted into the pin hole(311)located at the rotation axis of the first case(100), and functions as ashaft for the rotation axis of the side cover(300). The first case(100)comprises a pin groove(140), which is connected to a coil of the elasticpart(120). The pin(130) is inserted inside the coil from the pingroove(140).

FIG. 9 shows a support of a folding case according to an embodiment ofthe present invention. According to the FIG. 9, the support(150)comprises a closure(151). The closure(151) covers one side of the pingroove(140). Thus, the closure(151) functions to prohibit the pin(130)falling off the pin hole(311) and the coil. The pin(130) is insertedinside the coil and the pin hole(311), while being covered by theclosure(151), and functions as a shaft for the rotation axis of the sidecover(300). Thus, the side cover(300) may rotate by the hinge linkage tothe first case(100).

FIG. 10 demonstrates steps of connection between a first case(100) and aside cover(300) of a folding case(C) according to an embodiment of thepresent invention. According to FIG. 10, the elastic part(120) is firstlocated at one side of the first case(100). Next, the protrusion(310) ofthe side cover(300) is placed at the elastic part(120), in between thepair of torsion springs. Then, the pin(130) is inserted inside the coilof the elastic part(120) and the pin hole(311) of the protrusion (310)from the pin groove(140). When the support(150) is engaged on to theelastic part(120), the pin(130) inside does not fall off from theposition by the closure(151). The support(150) could be placed on thefirst case(100) by the linkage part(160). In an embodiment, the linkagepart(160) links the support(150) to the first case(100) with a screwlinkage. However, the linkage part(160) may also link the support(150)to the first case(100) in various ways other than the screw linkage.

FIG. 11 shows a folding case(C) in a closed state according to anembodiment of the present invention. FIGS. 12 and 13 show a foldingcase(C) in an open state according to an embodiment of the presentinvention. The side cover(300) rotates back to the first position by theelastic part(120). As demonstrated in FIG. 11, the side cover(300)maintains the first position by the elastic force of the elasticpart(120) when the folding case(C) is in a closed state by the foldablemobile device being folded. As in FIGS. 12 and 13, when the foldingcase(C) is in a open state by the foldable mobile device(M) unfolded,the side cover(300) tends to rotate back to the first position by theelastic force generated by the elastic part(120) twisted while the sidecover(300) is supported by the support(150). According to FIGS. 12 and13, the side cover(300) rotates with contacting tightly one side of thesecond case(200) by the elastic force of the elastic part(120). As aresult, the side cover(300) protects the hinge part(30), while rotating,by contacting tightly the second case(200) when the foldable mobiledevice(M) becomes folded or unfolded.

The degree of contact between the side cover(300) and the secondcase(200) is adjustable by the arm angle of the torsion spring in theelastic part(120). It is because the elastic force is dependent on thearm angle of the torsion spring. If the elastic force is too strong, itmakes it hard to open the fold case(C) since it is difficult to open theside cover(300). On the other hand, if the elastic force is too weak,the hinge part(30) of the foldable mobile device(M) could be exposed orthere would be a space between the side cover(300) and the secondcase(200) since the side cover(300) could not tightly contact to thesecond case(200). Thus, it is important to maintain the optimal elasticforce that enables the side cover(300) to contact the second case whilerotating. In an embodiment of the present invention, the arm angle ofthe torsion springs is 180°, but it can be modified depending on theelastic force.

FIG. 14 shows a bottom sectional view of a folding case(C) according toan embodiment of the present invention. Each of the side cover(300) andthe second case(200) comprises a curve(330, 220). The curve(330) of theside cover(300) is formed in a round shape at one corner that contactsthe second case(200). Similarly, the curve(220) of the second case(200)is formed in a round shape at one corner that contacts the sidecover(300). If the curves(330, 220) are not implemented at the portionwhere the side cover(300) and the second case(200) contact each other,the side cover(300) is not able to rotate over the second case(200)smoothly. As in FIG. 14, since the curves(330, 220) are implemented atthe portion where the side cover(300) and the second case(200) contacteach other, the portion where they contact is not plane-to-plane, butpoint-to-point, which makes the side cover(300) rotate over the secondcase(200) easier. In an embodiment, the R value of the curve(330) of theside cover(300) is larger than the R value of the curve(220) of thesecond case(200). The R value is a radius or rounding value, and itdefines how much the corner is rounded. If the R value of the curve(330)of the side cover(300) is larger, the side cover(300) is able to rotateover the curve(220) of the second case(200) easier. Thus, when thefoldable mobile device(M) is unfolded, it may provide the users withconvenience that comes from smooth rotation of the side cover(300) overthe second case(200).

In an embodiment, the R value of the curve(330) of the side cover(300)may be from 1 mm to 3 mm, and the R value of the curve(220) of thesecond case(200) may be from 0.5 mm to 2.5 mm. However, each R valuecould have a different value with the condition that the R value of thecurve(330) of the side cover(300) is larger than the R value of thecurve(220) of the second case(200).

FIG. 15 demonstrates that a side cover(300) of a folding case(C) is usedas a stand according to an embodiment of the present invention.According to FIG. 15, the side cover(300) may function as a stand.Depending on the position of the hinge part(30), the foldable mobiledevice(M) could be fixed in a position that it is folded or unfolded ina certain degree of angle. The side cover(300) rotates while thefoldable mobile device(M) is unfolded, where it generates a heightdifference from the surface of the first case(100). Due to such heightdifference, the foldable mobile device(M) may be in a higher positionwith the fold case(C), compared to without the fold case. Thus, the sidecover(300) may provide various angles of the stand depending on thedegree of folding or unfolding of the foldable mobile device(M).

FIG. 16 shows a button part of a folding case(C) according to anembodiment of the present invention. According to FIG. 16, the firstcase(100) comprises a first button part(170), and the second case(200)comprises a second button part(230). The button part may have a grooveor an opening at one side of the first case(100) and the secondcase(200), in order to press the button of the foldable mobile device(M)easily. In an embodiment of FIG. 16, the first case(100) has a groove onone side, while the second case(200) has an opening on the correspondingside. However, the button part may have various combinations of thegroove and the opening, not limited to the above, depending on theexterior design or the arrangement of the buttons of the foldable mobiledevice(M).

When the foldable mobile device(M) is in a folded state, the anglebetween each side of the first button part(170) and the second buttonpart(230) has a certain degree of angle. Depending on the embodiments, afoldable mobile device(M) may comprise a module or a button forverification that requires a direct contact with a body part of a user.If such a module or a button for verification is included, at least aportion of the button part should be open to allow the direct contact.However, on the other hand, as the display of a foldable mobiledevice(M) gets larger, it becomes more difficult to implement thefeature of an opening as the edge part(110) gets thinner so as not tointerfere with the display. It is because, if the area of the opening onthe edge part(110) becomes larger, it gets harder to maintain thedurability of a case. In order to maintain the durability of a case, oneof the first button part(170) and the second button part(230) is open,and the other is formed as a groove. However, if only one of the firstbutton part(170) and the second button part(230) has an opening, it isnot easy to press the button. The present invention forms a certaindegree of angle on one side of the button part of the first case(100)and the second case(200) to facilitate the direct contact to the moduleor button for verification of the foldable mobile device(M). By theformation of the designated degree of angle, it spontaneously leads thebody part to the button part. Therefore, the present invention may allowusers to press the button more easily due to the angle of the buttonpart, while maintaining the durability of the folding case(C).

When the foldable mobile device(M) is in a folded state, the anglebetween each side of the first button part(170) and the second buttonpart(230) may be from 150° to 160°, and preferably, 155°. It is derivedby the repetitive simulation, and it corresponds to the angle thatprovides the convenience for a user to easily contact the module or thebutton for verification.

The present invention, different from the previous folding cases,provides the full protection up to the corner of the hinge part(30), andat the same time, the portion that protects the hinge part(30) while thefolding case(C) is folded or unfolded without any unfavorable space orgap. Therefore, the present invention provides a full cover case thatprotects the entire foldable mobile device(M). In particular, the sidecover(300) of the present invention rotates with contacting tightly thesecond case(200) while the folding case(C) is folded or unfolded, andthereby, it provides the impression as if the first case(100) and thesecond case(200) form one united case. Also, the folding case(C)according to the embodiments of the present invention provides theoverall aesthetic appearance as the users would have the impression asif those parts form one united case by the side cover(300) while thefirst case(100) and the second case(200) are separated.

The description of the present invention as above is an exemplarydisclosure, and a skilled person in the art may be able to carry out thepresent invention with an obvious modification in various ways.Therefore, the scope of protection of the present invention is notlimited to the description and expression of embodiments. While theinvention has been shown and described with reference to differentembodiments thereof, it will be appreciated by those skilled in the artthat variations in form, detail, compositions and operation may be madewithout departing from the spirit and scope of the invention as definedby the accompanying claims.

The numbers and symbols used in the description and in the figures forthe present invention are summarized below:

C: a folding case;

10: a first body;

20: a second body;

30: a hinge part;

100: a first case;

110: an edge part;

111: a tunnel;

120: an elastic part;

121: a first torsion spring;

123: a second torsion spring;

125: a ring part;

130: a pin;

140: a pin groove;

150: a support;

151: a closure;

160: a linkage part;

170: a first button part;

200: a second case;

210: a bulge part;

220: a curve;

230: a second button part;

300: a side cover;

310: a protrusion;

311: a pin hole;

320: a cover part;

330: a curve;

400: air rooms; and

500: a pad part.

What is claimed is:
 1. A case for a foldable mobile electronic devicecomprising a first case and a second case, the case comprising: a sidecover that rotates from a first position to a second position along withthe rotation axis of the first case; and an elastic part that providesan elastic force that enables the side cover returns to the firstposition, wherein the side cover rotates as the foldable mobile deviceis folded or unfolded.
 2. The case of claim 1, wherein the first casecomprises a support that fixes at least a portion of the elastic part.3. The case of claim 2, wherein the elastic part comprises a pair oftorsion springs separated apart while being connected by an arm.
 4. Thecase of claim 3, wherein the pair of torsion springs comprises a firsttorsion spring and a second torsion spring that are positioned inparallel.
 5. The case of claim 3, wherein the elastic part comprises aring part that is formed by the pair of torsion springs that areconnected each other by the arm.
 6. The case of claim 5, wherein theside cover rotates back to the first position with the ring part beingsupported by the support.
 7. The case of claim 3, wherein the side covercomprises a protrusion which has a pin hole, and wherein a pin isinserted inside the pin hole and the elastic part, which enables theside cover to rotate based on the rotation axis of the first case. 8.The case of claim 7, wherein the protrusion is placed in between thepair of torsion springs.
 9. The case of claim 7, wherein the first casecomprises a pin groove that is connected to a coil of the elastic part,and wherein the pin is inserted from the pin inside the coil from thepin groove.
 10. The case of claim 9, wherein the support comprises aclosure that covers one side of the pin groove.
 11. The case of claim 1,wherein the angle between the first position and the second position isfrom 87 degrees to 93 degrees.
 12. The case of claim 1, wherein the sidecover comprises a cover part that covers up to the corner of the hingepart of the foldable mobile device.
 13. The case of claim 1, wherein theside cover comprises a curve that is formed in a round shape at onecorner that contacts to the second case.
 14. The case of claim 13,wherein the second case comprises a curve that is formed in a roundshape at one corner that contacts to the side cover.
 15. The case ofclaim 14, wherein a R value of the curve of the side cover is largerthan the R value of the curve of the second case.
 16. The case of claim1, wherein the first case comprises a first button part that has agroove or an opening at one side of the first case, and a second buttonpart that has a groove or an opening at one side of the second case, andwherein the angle between each side of the first button part and thesecond button part is from 150 degrees to 160 degrees when the foldablemobile device is in a folded state.